Heliotube concentrators have integrated tracking built into the panel, allowing more sunlight to reach a smaller photovoltaic surface area through the day.

The same size as conventional panels, it doubles efficiency by tracking the sun.

A Pasadena, Calif., company has applied to patent a new solar panel that can produce electricity at half the cost of conventional rooftop panels.

According to the MIT Technology Review, Soliant Energy's new Heliotube panel produces the same amount of energy as traditional solar arrays used in residential electrical systems, however a unique design reduces the amount of expensive photovoltaic material by almost 90 percent. Semiconductor-based photovoltaic (PV) material is needed to perform the actual conversion of solar energy to electricity inside a solar array, but the material is costly to produce.

Commercial solar energy production systems typically use mirrors and lenses to focus sunlight on the PV surfaces, making for more efficient energy production with a smaller PV surface area. In addition, panels are often mounted on posts that can pivot to follow the movements of the sun throughout the day, further concentrating the amount of sunlight reaching the PV material. However, these more efficient designs with moving mechanisms are impractical for smaller residential systems, which usually rely on a limited number of stationary, roof-mounted panels.

The Heliotube design incorporates lenses, mirrors and movable panels that track the sun. However, all of these components are encased in a rectangular acrylic case that is the same size as a conventional rooftop panel. The 50-pound panels are equipped with trough-shaped concentrators that move throughout the day. Aided by inexpensive optics, the mirrored troughs intensify the amount of sunlight reaching smaller PV strips located at the bottom of each trough.

The first-generation Heliotube panels, due to start shipping later this year, pivot only on one axis, limiting their ability to track the sun's movement. The company is designing a new version which will divide the troughs into shorter sections that can move independently to track the sun from side to side and from top to bottom, increasing the efficiency. The panels are self-powered and do not require alignment, according to the company.

Soliant's founder and CTO, Brad Hines, who formerly worked at Jet Propulsion Laboratory, said the company's goal is to offer consumers a "grid equivalent" cost of $0.06 per kilowatt hour in three years, not including tax incentives. "In industry terms, this means well under $1.50 per watt,” Hines said.